Figure 1From: Genome-scale metabolic network guided engineering of Streptomyces tsukubaensis for FK506 production improvementStructures and biosynthetic gene cluster of FK506 and byproducts (FK520, FK506D) in S. tsukubaensis . (A) Structures of FK506 and byproducts FK520, FK506D. The allyl side chain at C-21 of FK506 is replaced by an ethyl group in FK520 and a propyl group in FK506D. (B) Schematic representation of FK506 and analogues (FK520, FK506D) biosynthetic gene cluster in S. tsukubaensis.Back to article page